1. Field of Invention
The present invention relates to a cutting or severing apparatus or device for separating a quantity of floss material from its supply reservoir, and particularly to an apparatus or device for severing floss material made from expanded polytetrafluoroethylene (PTFE) fibers while also restraining the dental floss material in a manner that prevents the floss material from returning to its reservoir after severance.
2. Description of Related Art
Presently, there are a number of commercially available severing devices which are designed to sever dental floss and as well as to retain the unused portion of dispensed floss. An example is U.S. Pat. No. 4,050,648 to Tisma which teaches a floss dispenser system that maintains friction on the supply spool while the floss is dispensed. This prevents the unused floss from returning back to the floss supply spool after a section has been severed by a blade affixed to the dispenser. U.S. Pat. No. 5,199,622 to Vieau teaches a cantilever blade type cutter which has a depression or cutout element extending from the blade. The depression restrains the floss under the blade while the floss is cut by the perimeter. The entire perimeter of the blade is the cutting device. Unfortunately, with blade devices such as the one taught by Vieau, the floss material passes under the blade past the depression while the floss is dispensed. This may scrape away any coating, such as natural beeswax or medicament, which is deposited on the surface of the floss material. This unfortunate condition is further exacerbated when dispensing floss material made of expanded polytetrafluoroethylene (PTFE) such as taught in U.S. Pat. No. 5,518,012 to Dolan et al. The compressive nature of expanded PTFE permits the floss material to compress under the blade device into a denser filament, thus rendering the filament less effective to remove debris in the oral cavity during flossing.
A floss cutting device which does not compress the floss material prior to severing, does not remove coatings deposited on the floss material, restrains the severed end of undispensed floss, and provides a superior cutting device, would be desirable.
The present invention provides an improved cutting device for dental floss, and especially for highly compressible floss material such as floss material made of expanded polytetrafluoroethylene (PTFE), as well as coated, impregnated floss materials. The present invention also provides a cutting device with the added benefit of restraining the undispensed, severed end of dental floss using a novel technique not previously found in the art. The cutting device of present invention is mounted on a floss dispensing container in a location such that the user is able to easily position floss material dispensed from the supply spool under the blade and sever the floss.
The invention provides a device for severing and restraining a filament comprising a base having a restraining portion and a blade extending from the base, the blade having a first edge juxtaposed to the restraining portion of base to form a pinching element adapted to restrain the filament between the first edge and the restraining portion and a second edge adapted to sever the filament.
Also provided is a dental floss dispenser comprising a housing, a spool of dental floss disposed within the housing, and a device for severing and restraining the dental floss mounted on the housing, the device comprising a base having a restraining portion and a blade extending from the base, the blade having a first edge juxtaposed to the restraining portion of the base to form a pinching element adapted to restrain the filament between the first edge and the restraining portion and a second edge adapted to sever the filament.
The present invention is also suitable for use in severing fishing line, sewing thread, counted cross stitch floss, and other filaments which may be housed in a dispensing reservoir.